Coat the bottom of the pan with olive oil. Heat the pan on medium high heat until the oil is shimmering. Add the chopped onion and stir to coat the onions with the oil. Spread the onions out evenly over the pan and let cook, stirring occasionally for 8-10 minutes. Add a little bit of salt and pepper.

While onions saute, bring to a boil a vegetable stock; then reduce heat to maintain a steady simmer. Add carrots and potatoes. Simmer for 10-15 minutes
Clean and slice mushrooms, add to onions and fry for 5-7 minutes. Add onion-mushrooms mixture to stock with veggies and continue to simmer more 5-7 minutes.

While soup simmers, take dry small frying pan, add dry buckwheat groates and heat for 3-5 minutes. Buckwheat should be fried a little bit. Take off the frying pan from the heat and add buckwheat to a soup. Taste, add salt, pepper, chili-garlic sauce and chopped parsley. Add water and simmer for more 10-15 minutes. Taste again and adjust salt and pepper. Soup is ready. Soup tastes the best on next day.